Sub-atmospheric pressure indicating instrument



March 15, 1938. H. w. MITCHELL SUB-ATMOSPHERIC PRESSURE INDICATINGINSTRUMENT Filed NOV. 4, 1935 l. may] www@ 2 Patented Mar. 15, 1938SUB-ATMOSPHERIC PRESSURE INDIGATING INSTRUMENT Y Henry Walter Mitchell,Chicago, Ill.,\assignon toV Emil A. Stromberg, Chicago, Ill.

' Application November 4, 1935, SerialNo; l48,079

6 Claims.

The present invention relates to improvements in a portableindicatinginstrument ormancmeter employing a chart and having a vertical columncoacting therewith into which a fluid such as mercury, etc., is adaptedto be drawnto indicate `and check the suction qualitiesof varioussuction devices that may be attached thereto. l

The chief objects of the invention is the provision of an indicatingdevice which is simple in construction, strong and durable, inexpensivetomanufacture and accurate in operation, being easily attached tovarious suction devices to indicate the amount of suction producedthereby.

Another object is the provision of ka pair of charts arranged onoppositesides of a fluid column and visible on two sides of theinstrument `rendering the fluid level in the column readable on bothsides of the instrument during the checking operationsof the deviceattached thereto.`

A further object is the provision of a fluid container coacting with thefluid column which permits the iiuid therein to be easily drawn in theiiuid column and which is adapted to trap and withhold the iiuid thereinduring the transporting and handling of the instrument; to provide thecontainer with an air vent that is arranged and constructed to permit ofthe admission of air within the container while retaining the Iiuidtherein against accidental leakage.

And av further object is the provision of a manually controlled Valveforming a seal to trap the fluid within the container.

And a still further object is the provision of manually adjustablemagnifying means coacting with the fluid column and accessible outwardlyof the instrument for adjusting its position with, respect to the fluidlevel for rendering the same and the chart visible in enlarged scale.

Referring to the; drawing: v H Figure lis a detail perspective View ofthe lindicating instrument embodying my invention.

Figure 2 isan enlarged detail cross-sectional view taken substantiallyon the line 2-2 of Figure 1. p p

Figure 3 is an enlarged partial vertical medial sectional View takensubstantially on the line 3 3 of Figure l.

Figure 4 is a vertical sectional View taken substantially on the line4-4 of Figure 2` and partially broken away illustrating the ilexibleconnection from the transparent tubular member to the manuallycontrolled Valve.

`Figure 5 is a detail cross-sectional View of the fluid containerillustrating the position assumed by the fluid Vwhile in a horizontalposition'. Figure 6 is, a detail cross-sectional View of the uuidcontainer illustrating thepnsiuon assumed by the iiuid while in invertedposition; and

Figure 7 is a detail perspective View of the vent member associated withthe fluid container.

The refe-rence numeral lil designates the indieating instrument as awhole, comprising a casing H supported on a standard l2 provided with a`plurality o'f' horizontally disposed legs i3 that are veach providedwith a caster I4 rendering the instrument easily movable to be attachedto various devices.

The casing Il comprises the side walls l5 and i5 respectively, whicharen secured to the upper cap member I1 and tothe lowercap member i8 andhave the inwardlydi'rected V-shapedmembers i9 and 2li respectively,fixed` thereto which have their apexes directed toward each other and pform a space therebetween through which a transparent tubular member 2-lextends. The upper end of the tubular member 2l extends throughapartition wall`22 inthe caiga'member l l and has a ii'exiblctube23"`ccnnected thereto that is directed downwardlythrough thepartition wall 'Z2l and extends within the V-shaped member I9 andthrough-a partition wall 2li Xed in the lower capmember i8 and isconnected to a manually controlled valve 25.

The lower end of. the transparent tubular member 2| extends' centrallyof the instrument and through the partition wall 24 into a container 26that is'provided with an enlarged body portion 2Tv having a top Wall 28provided with an opening-'ZBt-llerein through which the tube 2l extendsand which is sealed in position therewith. The main body portion 2lofthe container has a bottom wall 3l) provided with an opening Slthereinadapted to receive a reduced body portion 32 which `is glued orotherwise secured in position andwhich has a bottom wall 33 adjaf centwhich the lower end of the transparent tubular memberZI extends. Thereduced body portion` (-32l o i the container 26 is secured to theenlarged body` portion 2l with its upper portion extending. about midwaytherein.` This reduced prtion 32 is provided with a plurality ofopenings Sii therein that are aligned with the inner sur- `ia'ce 35 ofthebottom wall 30 ofthe enlarged body portion 2l and serve to permit thefluid to ow from one portion to the other as the instrument is tilted. Afluid F such as mercury or the like, is placed within. the reduced bodyportion 32 through an opening 3l in the top wall 28 of the enlarged bodyportion 2l' of the container which is sealed against leakage of thefluidby means of a vent member 38 which has its inner end porbe below theslot opening 40 therein. (Figures ISO 3, and 6.) While I have shown thedevice employing a single vertical transparent column, a plurality ofcolumns may be employed and the container 26 for the fluid would beenlarged in proportion to the amount of fluid required to be drawn inthese columns when the device is being used.

As thus far described, it will be noted that the fluid F is normallyretained within the reduced portion 32 of the container 26 while theinstrument is in its normal upright position and the lower end of thetube 2| normally extends into the fluid and is provided with a bevelledannular edge 2 Ia to permit of a free and easy admittance of the fluidinto the tube. Should the instrument be placed on its side and thecontainer 26 assume the position as shown in Figure 5, the uid will thenrun out of the reduced portion 32 through the openings 34 into theenlarged portion 2l thereof, or should the instrument be inverted, thefluid will be carried from the reduced portion 32 to the enlargedportion 21 of the container as shown in Figure 6.

'I'he front and back walls 42 and 43 respectively, of the casing II arepreferably of transparentk material such as glass, etc., which is heldin position by means of the frame members 44 and 45 secured to the capmembers I1 and I8 by means of the screws 46 and 41.

The V-shaped portions I9 and 20 of the casing II each has a chart I9a or26a fixed thereon that extends its entire length and is provided withgraduations for indicating the fluid level within the transparent tube2I. Y

To render the uid level and the charts visible on an enlarged scale, Iprovide the lenses 48 and 49 arranged for vertical sliding movements onopposite sides of the tube ZI. These lenses are of sufficient size torender the charts and the Huid level in the tube visible therethroughand are carried on a frame member 50 that extends through an elongatedslot opening 36 in the V-shaped member 20 and through an elongated slotopening 5I in the side wall I6 of the casing II. 'I'he frame 5U isprovided with a hand grip 52 for positioning the lenses 48 and 49 to thevarious levels assumed by the fluid while checking different suctiondevices and for magnifying the charts and the fluid level rendering themreadily visible to the operator.

The valve 25 of the instrument is provided with a downwardly extendingportion 25a to which a suction device to be tested may be readilyattached. The valve 25 is then turned to open position permitting thesuction of the device to draw through theflexible tube 23 and thetransparent tubular member 2I to the container 26. This drawing actionto the container 26 causes the iluid F therein to be drawn into thetubular member 2I to an elevation equivalent to the suction produced bythe device and the fluid level is then registered by means of the chartsI9a and 20a. To more accurately check the reading of the charts with thefluid level, the lenses 48 and 49 may be moved by means of the hand grip52 and render the chart and uid level visible on an enlarged scale.

I contemplate as being included in these improvements, all such changes,variations. and departures from what is thus specifically illustratedand described as fall within the scope of the appended claims.

I claim:

l. An indicating instrument adapted to be connected to a suction devicefor determining the amount of suction produced thereby, comprising arectangular casing having transparent front and back Walls, a hollowtransparent column diposed substantially vertically therein, a containerfor a fluid attached to the lower end of the column and having a fluidtherein, a pair of vertically disposed V-shaped members having theirWalls converging toward the column and in opposed relation on each sidethereof, and a chart on each of said V-shaped members visible throughthe transparent front and back walls.

2. An indicating instrument adapted to be connected to a suction devicefor determining the amount of suction produced thereby, comprising acasing having open front and back walls, transparent plates enclosingthe front and back walls, a hollow transparent column disposedvertically in said casing and visible through the transparent plates ofthe front and back Walls, a container fixed to the lower end of saidcolumn and having a fluid therein, and a chart arranged on oppositesides of said column visible through the transparent front and backwalls of the instrument.

3. An indicating instrument adapted to be connected to a suction devicefor determining the amount of suction produced thereby, comprising acasing and a hollow transparent tube disposed vertically in said casing,a fluid container Xed to the lower end of said tube provided with a uidtherein, said container being arranged with upper and lowercompartments, said lower ccmpartment extending partially within theupper compartment and having a plurality of openings therein permittingthe fluid to flow from one compartment to the other when the instrumentis tilted.

4. An indicating instrument of the character described, comprising incombination, a casing having transparent front and back walls and opaqueside and top and bottom walls, a vertically disposed hollow transparentcolumn within the casing and visible through the front and back wallsthereof, a container for a fluid attached to the lower end of saidcolumn and having a fluid therein, a scale extending along each side ofsaid column and visible through the transparent front and back walls.

5. An indicating instrument adapted to be connected to a suction devicefor determining the amount of suction produced thereby, comprising acasing having transparent front and back walls, a transparent tubularcolumn disposed substantially vertically and centrally within thecasing, a container for a iluid attached to the lower end of the columnand having a fluid therein, said container being arranged with arelatively large upper compartment and a small lower compartment andwith the lower end of the tube extending into the lower compartment, anda chart on each side of the tube and visible through the transparentfront and back walls.

6. The combination of claim 5 hereof in which the lower compartment ofthe container is provided with openings therein permitting the liquid toow therethrough from said lower compartment to the upper compartmentwhen the instrument is tilted.r

HENRY WALTER MITCHELL.

